x1 is counterclockwise/left-turn-direction of[/to] x2 along/following track x3 [path] in frame of reference x4 (where the axis is within the region defined by the track as the boundary, as viewed from and defined by view(er) x4; see notes); x1 is locally to the left of x2, according to x4, constrained along x3; x1 is along a left turn from x2 along path x3, as viewed in frame x4.
Angular/curling direction: counterclockwise. The orientation of the path determines x4 but does not factor into consideration for x3. Further glosses: counterclockwise, locally leftward, left-turning (with no bulk translation) in a way that would be characterized as "positive" by the right-hand rule (aligned with and in the direction of a basis vector, at least for a given component). x1 is right-handedly/counterclockwise(ly) oriented relative to x2 on/along x3 in frame of reference x4 x1 is right-handed (one sense) from x2 [more accurately: moving from x2 to x1 requires a(n imaginary) motion that is right-handed along x3 as seen in frame/orientation/perspective x4]. x1 is to the path-following left of x2 (where the path is connected; as such, x1 is also be to the path-following right of x2, although there is an implication that the former is the smaller (or equal-length) path). See also: dutso, za'ei (vectorial cross product), zu'au (modal). Proposed short rafsi: -zuc-, -zu'a-. (If “zn” ever becomes a permissible initial consonant pair, krtisfranks proposes that “-zna-” become a rafsi of this word- it makes zucna and dutso more parallel in lujvo formation, and he is of the opinion that this word is useful and basic enough to warrant such a prized rafsi assignment; after this addition, the current two rafsi proposals can be done away with, reassigned, maintained, vel sim. as desired by the community at the time. In particular, he recognizes that “-zu’a-” might be confusing as a rafsi for this word while being a modal cmavo for zunle; but he does believe that this word deserves a vowel-final short rafsi.)